* @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.
   */
  @SuppressWarnings("unchecked")
  public static <T> Collector<T, ?, Optional<T>> toOptional() {
    return (Collector) TO_OPTIONAL;
  }

   * {@code null}!) before returning it to callers. Depending on how the code is structured, a
   * nullness analysis might not understand that the field has been populated. To avoid that problem
   * without having to add {@code @SuppressWarnings}, the code can call this method.
   *
   * <p>Why <i>not</i> just add {@code SuppressWarnings}? The problem is that this method is

     * @throws CIFSUnsupportedCryptoException if Provider has already been initialized.
     */
    public static void initProvider(final Provider customProvider) throws CIFSUnsupportedCryptoException {
        if (provider != null) {
            throw new CIFSUnsupportedCryptoException(
                    "Provider can't be re-initialized. Provider has already been initialized with " + provider.getInfo());
        }

func loadClusterUsageObjectMetrics(ctx context.Context, m MetricValues, c *metricsCache) error {
	dataUsageInfo, err := c.dataUsageInfo.Get()
	if err != nil {
		metricsLogIf(ctx, err)
		return nil
	}

	// data usage has not captured any data yet.
	if dataUsageInfo.LastUpdate.IsZero() {
		return nil
	}

	var (
		clusterSize               uint64
		clusterBuckets            uint64
		clusterObjectsCount       uint64

		// More than maxConfigSize bytes were available
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminConfigTooLarge), r.URL)
		return
	}

	// Ensure body content type is opaque to ensure that request body has not
	// been interpreted as form data.
	contentType := r.Header.Get("Content-Type")
	if contentType != "application/octet-stream" {
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrBadRequest), r.URL)
		return

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.hash;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;

import com.google.common.annotations.J2ktIncompatible;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * ImmutableSet implementation backed by a JDK HashSet, used to defend against apparent hash
 * flooding. This implementation is never used on the GWT client side.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
final class JdkBackedImmutableSet<E> extends IndexedImmutableSet<E> {

* The **database model** would probably need to have a hashed password.

/// danger

Never store user's plaintext passwords. Always store a "secure hash" that you can then verify.

If you don't know, you will learn what a "password hash" is in the [security chapters](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}.

///

## Multiple models { #multiple-models }

  public void testEquals_otherListContainingNull() {
    List<E> other = new ArrayList<>(getSampleElements());
    other.set(other.size() / 2, null);
    assertFalse(
        "Two Lists should not be equal if exactly one of them has null at a given index.",
        getList().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testEquals_containingNull() {

 *
 * <p>The {@code toString} method is forwarded to the delegate. Although this class does not
 * implement {@link Serializable}, a serializable subclass may be created since this class has a
 * parameter-less constructor.
 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingObject {

  /** Constructor for use by subclasses. */